Dudley Baldwin Bonsal (October 6, 1906 – July 22, 1995) was a United States federal judge.
Born in Bedford, New York, Bonsal received an A.B. from Dartmouth College in 1927 and an LL.B. from Harvard Law School in 1930. He was in private practice in New York City from 1930 to 1942. He was a chief counsel to the US Office of the Coordinator of Inter-American Affairs from 1942 to 1945, returning to private practice in New York City from 1945 to 1961, and from 1958 to 1960 served as president of the New York City Bar Association.
On October 5, 1961, Bonsal received a recess appointment from John F. Kennedy to a new seat on the United States District Court for the Southern District of New York created by 75 Stat. 80. Formally nominated on January 15, 1962, he was confirmed by the United States Senate on March 16, 1962, and received his commission on March 17, 1962. He assumed senior status on December 6, 1976. While in senior status, Bonsal was a judge on the Temporary Emergency Court of Appeals from 1977 to 1987, and on the Foreign Intelligence Surveillance Court from 1981 to 1984. Bonsal continued his senior service until his death, in 1995, in Bedford, New York.